| The purpose of this dissertation was to document the in vivo kinetics of heat shock protein (Hsp) 72 and interleukin (IL)-10 during heat acclimation (HA). Peripheral blood mononuclear cell (PMBC) and serum Hsp 72, and plasma IL-10 were measured pre- and post-exercise in 10 male and 2 female subjects (mean+/-SD, age: 24+/-4 years, VO 2max: 54.5+/-9.1 ml/kg/min, body fat: 13.6+/-7.6%) during a 10-day HA protocol. Subjects exercised at 56% of VO2max in a 42°C (28% RH) environment for 2 50-minute exercise bouts, separated by a 15-minute rest period. All sessions were completed in 2 weeks. PMBC were isolated before and after each acclimation session on days 1, 6 and 10. Plasma and serum were collected before and after exercise on the 1st and 10th day of HA. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used to determine PBMC Hsp 72 levels during HA and enzyme-linked immunosorbent assays (ELISA) were used to measure IL-10 and Hsp 72 concentrations.;To confirm that subjects were heat acclimated, duration, peak heart rate (HR), peak mean body temperature (MBT), and peak core body temperature (T c) were compared between days 1 and 10 of HA. Dependent t-tests indicated that peak HR, peak MBT, and peak HR were significantly lower on day 10 versus day 1, while mean duration was significantly higher on day 10 versus day 1. There was tendency for PBMC Hsp 72 to increase from pre- to post-exercise on the 1st day of HA (mean+/-SD, 1.0+/-0 vs. 1.6+/-0.6 density units, respectively, p=0.343). A one-way repeated measures ANOVA was used to show that pre-exercise Hsp 72 levels on day 1 were significantly lower compared to the pre- and post-exercise samples on days 6 and 10 (mean+/-SD, day 6: 2.1+/-1.0, 2.2+/-1.0, day 10: 2.0+/-1.3, 2.2+/-1.0 density units, respectively, p<0.05); samples analyzed on days 6 and 10 were not statistically different. There were no significant differences in serum Hsp 72 and plasma IL-10. The sustained elevation of Hsp 72 from days 6 to 10 may be evidence of a cellular HA process, and reveal the functional importance of Hsp 72 in physiological benefits of HA. |
